Heat setting and temperature indication in flatirons



Jana 1952 F. E. FINLAYSON 2, 4

HEAT SETTING AND TEMPERATURE INDICATION IN FLATIRONS Filed May 20, 1950 Inventor: Fran k' E, Finlagson,

His Attorhe5.. y

' and facilitate their use.

Patented Jan. 8, 1952 HEAT SETTING AND TEMPERATURE INDICATION IN FLATIRONS Frank E. Finl'ayson, Ontario, Califi, assignor to General. Electric Company, a corporation of New York Application May 20, 1950, Serial No. 163,185

4 Claims.

1 Myinvention: relates to automatic electric fiatirons; More particularly my invention relates to improvements'in heat setting. and heat conditi'on indicating arrangements for automatic flatirons- It should be understood thatautomatic electric fiatirons provide setting'of the ironfor a desired operating temperature and: automatic maintenance ofthat temperatureby the iron. However, when the iron is cool, that is, at the beginning of a'peri'od of use of the there is an appreciable time interval between the connection of the iron to'th'epower source and the attaim ment or the setting heat by the iron. Also if the setting or an iron ischangedduring opera tron, there is a time lag between the 'instant'of changing'the setting and the actual heating up or cooling down of the'iron to match that setting. Therefore; some irons are providednot only with an indication to'the user of the heatsetting, but also with'an indication of the condition or tem perature of'the iron relative to that setting. By this meansan operator can tell whethercr not the'iro'n is above or below or atthe proper operating'temperature.

The present invention is directed toward improvements in the heat setting and heat indicating arrangement for electric flatirons. One object of my invention is to provide heat setting and temperaturei'ndicating mechanisms of a novel "character. These improvements promote theease of manufacture oi'devices of this-type Another object is to increase the visibilityof the indicators for both the heat setting and temperature reading. A still further object is to avoid expensive oonstructi'ons so that heat setting and indicating mechanisms according to myinventicn may be made economically andhave ahigh degree of dependability in use over a long period of time. According to one aspect of my invention, the coordinated calibration of the indicator and or the heat setting control is made easy. Protection of sensitive parts from accidental damage is. another object ofthe invention. Improved appearance'o'f heat setting and indicating devices in flatirons maybe a further result of my invention.

The principal objects of my invention. are met by placing the heat setting indicator and the temperature. indicator both at the top of the iron at the front of the handle where they are visible. at all times whether the iron is in horizontal position or if it is tilted backwardly on to its usual heel stand. Other objects and the details of that which I believe to be novel. and my in vention will be clear from the following description and claims taken with the accompanying drawing in which is illustrated an exampIe o f a device embodying the present inventionand incorporating my novel heat setting indication and temperature indication mechanisms. 7

In the drawing Fig. 1 is a side view largely in cross section showing the interior parts of an electric fiati'ron; Fig. 2 is a plan view onan enlarged scale of the front end of the iron oiv Fig. 1

with certain parts broken away for clarity in illustration,v and Fig. 3 is an enlarged vertical'secti'on through the essential movable parts of the heatsetting and temperature indication mocha ni'sms of Fig. 1. I

As shown, an iron according to my invention has the usual sole plate I with'a suitable heating element such as the one shown. at 2 which may be embedded therein. The body of the. iron proper is completed by the cover or'shell'iwhich extends over the sole plate and may project rearwardly therefrom in a heel portion 4, the bottom of which may be closed as by a bottom heel cover plate 5.

The usual handleifor the iron has a horizontal hand grip portion 6 with a vertically extending post .1. at the front of the iron, and a correspondingpost 8at the back of the iron. Thehandle is shown here as secured to the body of the iron at the front as by the bracket 9, brazed, welded or otherwise suitably-secured to the shell, and by the screw lllpassing through an extension on this bracket and threaded into the bottom of the post I. The rear post of the handle may also be shit: ably secured to the iron in any desiredfashion. I have not shown the customary electrical conmotions to the heating element within the iron although these maybe brought into the back post 8 which may be made hollow for that purpose.

, It will be noted that when the iron is tipped backwardlyvv it. rests .on the heel rest t and on the tip of the back post of the handle, being supported by an ironing board or other surface S (see dot-dash .line in Fig. 1) as is common with electrical flatirons. It is also usual in'automatic electrical flatirons to have an electrical control switch of suitable character which will open the circuit to the heating element when the iron has attained .the desired operating temperature. 'I have shown a thermostatic control switch H- with contacts i2 and IS, the contact B being moved away from the contact [2 upon the flexing of a bimetallic strip H! which is suitably secured within the iron body. The position of the two contacts relative to each other, and therefore the temperature at which the two contacts will separate to break the circuit to the heating element, is governed bythe position of a temperature setting control lever arm IS. The forward tip of this switch controlling arm rides on rotatable cam member l6, which is suitably supported within the chamber under the shell as by the Z-shaped bracket ll. Rotation of the cam I6 about its vertical axis on the supporting bracket I! will change the position of the arm 25 and and assigned to the same assignee as the present 1 application. Obviously thermostatic switches and controls of other design could be used according to the present invention.

Rotation of the cam l6 and therefore regulation of the setting of the switch II is controlled manually by rotation of a control shaft or mechanism shown here as a vertically extending tubular member l8 suitably secured at its bottom end to the cam l6, and extending through a hole l9 in the shell 3 to the outside of the iron body. The rotational position of this tubular shaft is controlled by the angular position of the horizontally extending lever control arm. which has a handle or finger piece 2| at its outer end. The inner end of this lever arm is, of course, secured to the tubular member [8, as by the small lug 22 on the arm which rides in theslot 23 in the tubular member. Pivotal mounting for the lever arm and for the tube may be obtained through the cooperation of a dished portion 24 on the lever arm with a boss 25 on the bottom of the handle post 1, or in any other desirable fashion.

Heat setting indications, which may take the form of fabric markings, may be placed on the body of the iron opposite the various positions of movement of the handle piece 2| for the thermostat control lever. However, I prefer to place these fabric markings on top of the handle of the iron at the front as shown best in Fig. 2. The fabric markings for indication of the heat setting might be embossed upon or impressed in the material .of the handle itself, but I prefer to use a separate indicating piece in the form of a wafer 26 having a beveled edge 21' on which the various indications such as 28 are marked. This fabric marking wafer may be slipped into a slot 29 in the front of the top of the handle and cemented in place or held in place by the mechanisms about to be described.

The front post of the handle is made hollow to provide a vertically extending passageway 39 between the slot 29 and the base of the post for receiving the upper end of the tubular member l8 and other parts for indicating the heat setting. As shown best in Fig. 3 the tube l8 has secured at its top a circular disc member in the form of a hollow shell 3| having a pointer 32 extending from one portion of the edge thereof. Radially opposite this pointer is a small window 33 for purposes which will appear later. With this arangement, as the tubular shaft I8 is rotated by movement of the arm 20, the disc like shell 3| will also rotate and move the pointer 32 opposite any desired one of the heat setting markings 29; at the same time the thermostatic switch will be adjusted so that the flat iron will operate at approximately the desired temperature for the marking selected. However, as pointed out above, this does not insure that the iron will always be at the selected temperature and therefore I have provided a heat indicating or temperature reading mechanism whichis used in connection with the heat setting indicator to show when the iron is at the proper operating temperature.

The temperature indicating mechanism is driven by a coil or spiral of bimetal 34 mounted in a cavity 35 in the sole plate of the iron directly underneath the end of the passageway 39 of the handle. The bimetal is secured at its outer end to a support 36 which in turn is forced or otherwise secured within the cavity 35. The central end of the bimetal spiral is connected as by a slot 31 to the bottom of a rod 38 which passes rotatably through a central hole in the bimetal supporting member 36. Upon bending of the bimetal 34, caused by heating or cooling of the bimetal by the heating element inthe sole plate, the rod 38 will'be rotated in one di-' rection or another about its vertical axis;

This rod carries at its top end a circular temperature indicating disc 39 which is mounted to rotate freely inside of the shell 3|. The upper end of the rod 38 and the center of the temper ature indicating disc 39 are secured together preferably by a bearing piece 40 having an upper point or tip 4| rotatably seated within a hole or recess 42 in the center of the top of the shell 3|. Portions of the temperature indicating disc 39 are visible at all times through the window 33 in the shell and I prefer that the temperature indication be made in the form of different colors which are printed or otherwise applied to the disc 39 on the areas which will be exposed under the window 33. For instance,ithe color yellow might be selected for one area on the disc 39 to indicate that the iron has reached a temperature satisfactory for the heat setting opposite the window. The color red might be used to indicate a temperature of the iron above the setting. The color blue might be used to show that the iron was below the temperature at which it was desired to Op a Fig. 2 shows the position of parts as they would appear if the iron had been operating at the high Linen heat setting and had reached proper temperature, and the heat control setting had just been changed to the lower setting between Wool and Rayon but the iron had not yet cooled. The temperature indicator shows red under the window, informing the operator that the iron is too hot for the new setting.

Naturally, the correct temperature setting indicating area might utilize a color different than yellow, and other colors might also be used in place of the red and bluementioned above. However, whatever color is used, the colored area which is to indicate proper operating temperature of the iron is placed between the other two colors around the circumference of the disc 39 and usually, if not always, should be made of less angular extent around the circumference. Therefore, after the iron heat control has been set at the desired temperature, the color viewed through the window 33 opposite the pointer will indicate to the user whether the iron is above, below, or within the range of the proper ironing temperature.

Spring washers such as those at 43 and may be used to restrain the tubular shaft l8 and the rod 38 from unwanted movement, and in troduce a slight amount of friction in the opera tion of these parts so that they will not slide around in an undesirable fashion.

. Bccause'the-discshe ll extends through the not in the front and top of the handle post of j the iron, 'both'theheat setting: and temperature indicating devicesare visible at the top andfront f of the 'ircn ha-n'dlev These may therefore be seen by the user not only when the iron is' in horizontal or-ironing position but also when the iron is tilted backwardly toward the rest posilimited to the particular details of construction of the exampleillustrated'and I contemplate that various and other modifications'and applications of'thcinvention will occur tothosc skilied'inthe art. Itis,'theref'orc, my intention that the appended claims shall cover such modificationsxa-nd ti'onon thesupporting surface S while 'the'user is waiting forithe-iron' to heat upor cool down to.

operating conditions permit. Absolute accuracy of calibration is not necessary inmanufacturebecausev a wide corrcctoperating temperatureindicatin'g area willcompensate "for considerable error in ad' ustment ofthe parts. Absolute 'accuracy of calibration is not needed in use of the device, because the two indications are used only on a comparative basis, that is, any heat setting covers a range of several degrees of temperature of the desirable results, and therefore the registry of the window 33 with a particular color segment on the disc 39 need not be absolute or precise in nature. It is enough if the temperature indicator shows the general condition of the iron within a comparatively broad heat setting range.

If desired, the entire top of the shell disc may be made of transparent material, instead of using the window opening 33. In this case, the operator can watch the progress of the temperature indicating color disc, and thus may be able to judge when the iron is approaching close to the heat setting. This is useful in cases where a precise temperature is not regarded as necessary for a particular article being ironed.

The circular disc or shell-like nature of both applications as donot depart from the true-spirit and: scope of my: invention.

What! claim as .new and desire to secure by Letters Patent of the United States is;

1. In an automatic electric flatiron of the type having-an ironing body with a'heating element therein, a thermostatic control "ior'maintainin a given temperature for said element, manually operable heat setting means for altering said control for the production of selected degrees of heat in the iro'n,;and a'handle securedtosaid ironing 'body with a "vertically extending post near "the'front of said iron, that improvement ina heat setting and heat indicating arrange- 'ment for the iron comprising a vertically extending passagewayin said post opening at the top and front thereof, a rotatable 'hollowcircular shell mounted for rotation about a central vertical axis at the top of said post, a vertically extending tubular shaft fixed to said shelland extending through said passageway into said ironing body; means connecting the "lower end of said tubular shaft to said heat setting means, a thermally responsive member in said ironing body movable in response to the temperature of said heating element, a vertically extending rotatable rod secured to said thermally responsive member at its lower end and extending from said member through said passageway inside of said tubular shaft, and a circular disc shaped indicator at the top of said shaft within said shell, said shell being provided with a transparent window for observing the position of said disc.

2. In an automatic electric flatiron of the type having an ironing body with a heating element the member 3| and the member 39 insures that,

the heat setting and temperature indicating.

members will be in proper mechanical balance at all times. The pointer may be a spot marking on a continuous circumferential flange projecting from the shell, instead of a radial point as shown, further balancing the mechanical structure.

The mounting of the entire temperature indi-' cating mechanism, including its operating shaft or rod as well as its indicating disc, entirely withl in the tubular operating shaft and the heat set ting indicating shell of the thermostat control mechanism insures that the temperature indi-f' cating mechanism will not be damaged either ac cidentally or by malicious design. In order to prevent any possible touching of the disc 39 from outside of the window 33 as by a pencil or other sharp instrument, the window 33 may be made preferably as a transparent section of the shell 3| and need not be an open hole. In this case 3|, preferably on its inside surface. If the shell is made of opaque material, the window may be covered by a transparent sheet on the inside or outside.

As will be evident from the foregoing description certain aspects of my invention are not therein, a thermostatic heating element control for automatically maintaining a selected temperature of said body by closing and opening the electrical circuit to said heating element, manually operable heating setting means for altering said selected temperature and a handle secured to said bodyincluding a front supporting post therefor, that improvement comprisin a passageway in said post extending from said ironing body to the top of said post and having an opening at the front thereof, a rotatable heat setting indicator in the formof a hollow circular shell located at and visible through said opening, a rotatable hollow shaft for said indicator shell extending through said passageway and connected to said heat setting means to amove therewith, a temperature indicator in the form of a circular disc rotatably mounted within said heat setting indicator shell, said indicator shell having a window through which the circular disc is visible, a rotatable rod for said temperature indicator disc mounted coaxially within and free to move independently of said hollow shaft, and means responsive to the temperature of said ironing body connected to said shaft for turning the shaft to position said inthe rest of the shell 3| is made opaque as by painting, frosting or otherwise treating the shell 3 dicator disc.

3. In an automatic electric flatiron of the type having an ironing body with a heating element therein, a heating element control for maintaining a selected temperature of said body by closing and opening the electrical circuit to said heating element in response to temperature changes of said element, manually operable heat setting means for altering said selected temperature and a handle secured to said body includtoward thetop of said post and having an opening near the top of said postat the front of said handle, a heat setting indicator in the form of a hollow shell rotatably mounted about a vertical axis in'and visible through said openin a hollow driving shaft fixed to said indicator shell and extending vertically throughsaid pas sageway, a lever arm extending from said drivingshaft, adapted for manual rotation of said shaft and simultaneous operation of said heat setting means, a temperature indicator in the form of a disc rotatably mounted within said shell, a viewing window in said shell above said temperature indicating disc, 9, driving rod for said temperature indicator disc rotatably mounted coaxially within said hollow driving shaft and a temperature responsive element in said ironing body connected to said driving rod to rotate it in response to temperature changes in said bo y the temperature of the ironing body, manually operable means foradjusting the settingof said thermostat, and a handle for the body, a heat setting and temperature indicator comprising heat setting indicia on said handle, a hollow shell rotatably mountedin said handle adjacent said indicia, means connecting said shell to said man.- ually operable means, a pointer on the circumference of said shell'co-operating with said indicia for indicating heat settings of said fiatiron; a window'in said shell located radially opposite said pointer, a temperature indicating disc rotatably mounted Within said shell, having temperature indicating areas visible through window, and means responsive to the temperature of the ironing body for positioning said indicating disc. FRANK E.'FI1\TLAYSON.

REFERENCES CITED The following references are'of record in the file of this patent: I

UNITED STATES PATENTS Finlayson June 15, 1948 

